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Finance and Economics Discussion Series Divisions of Research & Statistics and Monetary Affairs Federal Reserve Board, Washington, D.C. Is Economics Research Replicable? Sixty Published Papers from Thirteen Journals Say ”Usually Not” Andrew C. Chang and Phillip Li 2015-083 Please cite this paper as: Chang, Andrew C., and Phillip Li (2015). “Is Economics Research Replicable? Sixty Pub- lished Papers from Thirteen Journals Say ”Usually Not”,” Finance and Economics Dis- cussion Series 2015-083. Washington: Board of Governors of the Federal Reserve System, http://dx.doi.org/10.17016/FEDS.2015.083. NOTE: Staff working papers in the Finance and Economics Discussion Series (FEDS) are preliminary materials circulated to stimulate discussion and critical comment. The analysis and conclusions set forth are those of the authors and do not indicate concurrence by other members of the research staff or the Board of Governors. References in publications to the Finance and Economics Discussion Series (other than acknowledgement) should be cleared with the author(s) to protect the tentative character of these papers.
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Page 1: Is Economics Research Replicable? Sixty Published Papers ... · Is Economics Research Replicable? Sixty Published Papers from Thirteen Journals Say ”Usually Not” Andrew C. Chang

Finance and Economics Discussion SeriesDivisions of Research & Statistics and Monetary Affairs

Federal Reserve Board, Washington, D.C.

Is Economics Research Replicable? Sixty Published Papers fromThirteen Journals Say ”Usually Not”

Andrew C. Chang and Phillip Li

2015-083

Please cite this paper as:Chang, Andrew C., and Phillip Li (2015). “Is Economics Research Replicable? Sixty Pub-lished Papers from Thirteen Journals Say ”Usually Not”,” Finance and Economics Dis-cussion Series 2015-083. Washington: Board of Governors of the Federal Reserve System,http://dx.doi.org/10.17016/FEDS.2015.083.

NOTE: Staff working papers in the Finance and Economics Discussion Series (FEDS) are preliminarymaterials circulated to stimulate discussion and critical comment. The analysis and conclusions set forthare those of the authors and do not indicate concurrence by other members of the research staff or theBoard of Governors. References in publications to the Finance and Economics Discussion Series (other thanacknowledgement) should be cleared with the author(s) to protect the tentative character of these papers.

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Is Economics Research Replicable?Sixty Published Papers from Thirteen Journals Say

“Usually Not”

Andrew C. Chang∗and Phillip Li†

September 4, 2015

Abstract

We attempt to replicate 67 papers published in 13 well-regarded economics journalsusing author-provided replication files that include both data and code. Some journalsin our sample require data and code replication files, and other journals do not requiresuch files. Aside from 6 papers that use confidential data, we obtain data and codereplication files for 29 of 35 papers (83%) that are required to provide such files as acondition of publication, compared to 11 of 26 papers (42%) that are not required toprovide data and code replication files. We successfully replicate the key qualitativeresult of 22 of 67 papers (33%) without contacting the authors. Excluding the 6 papersthat use confidential data and the 2 papers that use software we do not possess, wereplicate 29 of 59 papers (49%) with assistance from the authors. Because we areable to replicate less than half of the papers in our sample even with help from theauthors, we assert that economics research is usually not replicable. We conclude withrecommendations on improving replication of economics research.

JEL Codes: B41; C80; C82; C87; C88; E01Keywords: Data and Code Archives; Gross Domestic Product; GDP; Journals;

Macroeconomics; National Income and Product Accounts; Publication; Research; Repli-cation

∗Chang: Board of Governors of the Federal Reserve System. 20th St. NW and Con-stitution Ave., Washington DC 20551 USA. +1 (657) 464-3286. [email protected]://sites.google.com/site/andrewchristopherchang/.†Li: Office of the Comptroller of the Currency. [email protected].‡The views and opinions expressed here are those of the authors and are not necessarily those of the

Board of Governors of the Federal Reserve System, the Department of the Treasury, or the Office of theComptroller of the Currency. We thank B.D. McCullough, Bo Sun, and Kurt von Tish for helpful comments.We thank Tyler J. Hanson, Erik Larsson, Kim T. Mai, Anthony Marcozzi, Shawn M. Martin, Tyler Radler,Adam Scherling, and John Stromme for research assistance. We also thank Felix Galbis-Reig and SpencerC. Li for technical assistance. We are responsible for any errors.

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1 Introduction

In response to McCullough and Vinod (2003)’s failed replication attempt of several articles in

the American Economic Review (AER), then-editor of the AER Ben Bernanke strengthened

the AER’s data and code availability policy to allow for successful replication of published

results by requiring authors to submit to the AER data and code replication files (Bernanke,

2004). Since the AER strengthened its policy, many of the other top journals in economics,

such as Econometrica and the Journal of Political Economy, also started requiring data and

code replication files.

There are two main goals of these replication files: (1) to bring economics more in line

with the natural sciences by embracing the scientific method’s power to verify published

results, and (2) to help improve and extend existing research, which presumes the original

research is replicable. These benefits are illustrated by the policy-relevant debates between

Card and Krueger (1994, 2000) and Neumark and Wascher (2000) on minimum wages and

employment; Hoxby (2000, 2007) and Rothstein (2007) on school choice; Levitt (1997, 2002)

and McCrary (2002) on the causal impact of police on crime; and, more recently, Reinhart

and Rogoff (2010) and Herndon, Ash, and Pollin (2014) on fiscal austerity. In extreme cases,

replication can also facilitate the discovery of scientific fraud, as in the case of Broockman,

Kalla, and Aronow (2015)’s investigation of the retracted article by LaCour and Green

(2014).

This article is a cross-journal, broad analysis of the state of replication in economics.1

We attempt to replicate articles using author-provided data and code files from 67 papers

published in 13 well-regarded general interest and macroeconomics journals from July 2008

to October 2013. This sampling frame is designed to be more comprehensive across well-

regarded economics journals than used by existing research. Previous work has tended to

focus on a single journal, such as McCullough, McGeary, and Harrison (2006), who look1We follow existing work by, among others, Dewald, Thursby, and Anderson (1986); McCullough and

Vinod (2003, 2004); McCullough, McGeary, and Harrison (2006); Hamermesh (2007) and Glandon (2010).

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at the Journal of Money, Credit and Banking (JMCB); McCullough and Vinod (2003),

who attempt to replicate a single issue of the AER (but end up replicating only Shachar

and Nalebuff (1999) with multiple software packages); or Glandon (2010), who replicates a

selected sample of nine papers only from the AER.

Using the author-provided data and code replication files, we are able to replicate 22 of

67 papers (33%) independently of the authors by following the instructions in the author-

provided readme files. The most common reason we are unable to replicate the remaining 45

papers is that the authors do not provide data and code replication files. We find that some

authors do not provide data and code replication files even when their article is published in

a journal with a policy that requires submission of such files as a condition of publication,

indicating that editorial offices do not strictly enforce these policies, although provision of

replication files is more common at journals that have such a policy than at journals that do

not. Excluding 6 papers that rely on confidential data for all of their results and 2 papers

that provide code written for software we do not possess, we successfully replicate 29 of 59

papers (49%) with help from the authors. Because we successfully replicate less than half of

the papers in our sample even with assistance from the authors, we conclude that economics

research is usually not replicable.2

Despite our finding that economics research is usually not replicable, our replication

success rates are still notably higher than those reported by existing studies of replication

in economics. McCullough, McGeary, and Harrison (2006) find a replication success rate

for articles published in the JMCB of 14 of 186 papers (8%), conditioned on the replicators’

access to appropriate software, the original article’s use of non-proprietary data, and without

assistance from the original article’s authors. Adding a requirement that the JMCB archive

contain data and code replication files the paper increases their success rate to 14 of 62

papers (23%). Our comparable success rates are 22 of 59 papers (37%), conditioned on our2This result is in line with recent evidence in replicating psychology studies by Open Science Collaboration

(2015), where the authors fail to replicate the qualitative result of the majority of their sample of psychologyexperiments.

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having appropriate software and non-proprietary data, and 22 of 38 papers (58%) when we

impose the additional requirement of having data and code files. Dewald, Thursby, and

Anderson (1986) successfully replicate 7 of 54 papers (13%) from the JMCB, conditioned on

the replicators having data and code files, the original article’s use of non-confidential data,

help from the original article’s authors, and appropriate software. Our comparable figure is

29 of 38 papers (76%).

2 Methodology and Sampling Frame

Our sampling frame includes papers from 13 well-regarded macroeconomics and general

interest economics journals: American Economic Journal: Economic Policy, American Eco-

nomic Journal: Macroeconomics, American Economic Review, American Economic Review:

Papers and Proceedings (P&P), Canadian Journal of Economics, Econometrica, Economic

Journal, Journal of Applied Econometrics, Journal of Political Economy, Review of Eco-

nomic Dynamics, Review of Economic Studies, Review of Economics and Statistics, and

Quarterly Journal of Economics. We choose papers from these journals because of the rela-

tive likelihood that such papers will have a policy effect and also influence future research.3

We do not select these journals to single out a particular author, methodology, institution,

or ideology.

From our sample of journals, we browse for original research articles published in issues

from July 2008 to October 2013.4,5 Within these issues, we identify all papers with the

following three characteristics: (1) an empirical component, (2) model estimation with only

US data, and (3) a key empirical result produced by inclusion of US gross domestic product3For example, according to the 2014 social science edition of Thompson Reuters Journal Citation Reports,

these journals represent half of the top 10 impact factor journals in economics and, aside from the CanadianJournal of Economics, all journals are in the top impact factor quartile for economics.

4This definition excludes lectures, symposiums, and literature reviews. We also exclude articles publishedprior to July 2008 when a comment on the article is published on or after July 2008.

5We choose an arbitrary start date of July 2008. We select the end date of October 2013 to match whenwe began this project.

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(GDP), published by the Bureau of Economic Analysis (BEA), in an estimated model.6 We

choose to focus on GDP because of its status as a standard macroeconomic statistic and its

widespread use in research.7

For each paper in this set, we attempt to replicate the key empirical results.8 We focus

on the key empirical results for two reasons: (1) replicating only the key results allows us to

expand the sample to more papers, and (2) the key result of the paper is presumably what

drove the paper’s publication; robustness checks merely serve as confirming evidence.

Defining a key result is subjective and requires judgmental decisions on our part. We

attribute a key result of the paper to GDP when the authors themselves refer to GDP

as driving a key result, or when a discussion of GDP is featured either in the abstract or

prominently in the introduction of their work (or both). We also take key results as those

that appear in figures and tables.9

We find 67 papers that fit these criteria. Of these papers, 6 papers use proprietary

data for all of the key results, so we do not include them in our replication exercise (Fisher

and Peters, 2010; Alexopoulos, 2011; Alexopoulos and Cohen, 2011; Hall and Sargent, 2011;

Bansak, Graham, and Zebedee, 2012; Gilchrist and Zakrajšek, 2012). If a subset of the key

results could be obtained using non-proprietary data, then we attempt to replicate those

results.

For the remaining papers that use public data and are published in journals that maintain

data and code archives, we download the replication files provided by the authors through the

online archives provided by the journals. Unlike prior work by McCullough, McGeary, and

Harrison (2006), who found difficulty in accessing the archives of selected journals, we had6The authors may calibrate a subset of their model’s parameters and still have their paper fall within our

sample. We exclude papers that have only completely calibrated models.7Several of the most cited articles in economics use GDP or its predecessor gross national product (GNP)

(Sims, 1980; Kydland and Prescott, 1982; Barro, 1991; Hodrick and Prescott, 1997). Recognizability of GDPextends to the popular press as well. For example, on the HBO late-night talk show “Last Week Tonight,”John Oliver cites GDP as a measure of the importance of the District of Columbia (Last Week Tonight,2015).

8A paper’s primary contribution may be theoretical, but we focus only on the empirical component.9The web appendix details what we interpret as the key result of every paper in our sample and is available

on Chang’s website, https://sites.google.com/site/andrewchristopherchang/research.

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no trouble doing so through the Board of Governors of the Federal Reserve System or Office

of the Comptroller of the Currency subscriptions. However, consistent with McCullough,

McGeary, and Harrison (2006), we find that journal data and code archives are incomplete.

Of the 35 papers that use public data and are published in journals that require data and

code replication files, we obtain files for 28 papers (80%) from journal archives.

For papers where we are unable to obtain replication data and code files from journal

archive sites, either because the mandatory files are is missing or because the paper is not

subject to a data availability policy, we check the personal websites of each of the authors

for replication files. If we are unable to locate replication files online, then we email each of

the authors individually requesting the replication files.10 Of the 7 papers that use public

data, are subject to a data and code policy, and do not have replication files on the journal’s

archive site, this procedure nets us one additional set of replication files. Therefore, we are

unable to locate replication files for 6 of 35 papers (17%) that are published in journals

that require submission of data and code replication files. For papers published in journals

without a data and code availability policy and that use public data, we are unable to obtain

data and code replication files for 15 of 26 papers (58%). We do not single out any paper or

author that fails to comply with a journal’s mandatory data and code policy. We therefore

only report these summary statistics of compliance with data availability policies and only

cite papers that we either successfully replicate, that use proprietary data, or where we have

what appears to be a complete set of replication files in a software we do not possess. Our

intention is to highlight the general state of replication files for published economics research,10We email each of the authors sequentially using the email addresses obtained in the following three-

step manner, moving down a step when our email was undeliverable: (1) the address listed on the author’spersonal site, (2) the address listed on the author’s current institution’s site, and (3) the address listed withthe published paper. We wait at least one week between contacting each author. If a corresponding authoris listed on the paper, then we start with contacting the corresponding author and work our way through theauthors in the order they are presented in the paper. If there is no corresponding author, then we initiatecontact with the first author. We stop querying different authors to request data and code after receiving aresponse from any author, unless we are specifically directed to by an author we had already queried or wefail to receive a response after an author-requested delay. We mark the data and code files as incompletewhen we both are unable to locate a complete set of files online and also do not receive a complete set of filesin response to our emails after waiting a minimum of one month for each author to respond to our queries.We stopped considering responses as of July 15th, 2015.

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not to berate any given author, methodology, institution, or ideology.

To determine whether a paper was subject to a data availability policy, we check the

implementation dates of the journal data policies and compare them to the publication and

submission dates of the published work. If the journal’s website does not allow us to extract

this information, then we query the editorial office as to when their data availability policy

became effective. We do not ask the editorial offices whether a particular paper was subject

to a data availability policy. Aside from papers with proprietary data, we find that journal

data archives do not provide lists of potentially exempt papers. Therefore, we are unable

to determine whether a paper is exempt for a reason other than using proprietary data,

although we are not aware of reasons why journals would grant a paper a data and code

exemption other than for proprietary data. The authors we query whose papers we believe

are subject to a data availability policy yet whose replication files we are unable to locate

do not volunteer whether their papers are exempt from the policy, and we do not ask the

authors for this information.

For the papers for which we are able to obtain data and code replication files, we attempt

to replicate the key results of the paper using only the instructions provided in the author

readme files. If the readme files are insufficient or if the replication files are incomplete

(or both) and the paper is subject to a replication policy, then we email the corresponding

author (if no corresponding author, then the first author) for either clarification or to request

the missing files. If we do not receive a response within a week, then we query the second

author, and so on, until all authors on the paper had been contacted.11

We define a successful replication as when the authors or journal provide data and code

files that allow us to qualitatively reproduce the key results of the paper. For example,

if the paper estimates a fiscal multiplier for GDP of 2.0, then any multiplier greater than

1.0 would produce the same qualitative result (i.e., there is a positive multiplier effect and11If we already contacted the authors to request data or code but were having difficulty executing the

code, then we only queried the authors whom we did not yet contact. We initiate contact with each authora maximum of one time.

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that government spending is not merely a transfer or crowding out private investment).12

We define success using this extremely loose definition to get an upper bound on what

the replication success rate could potentially be.13 We allow for minimal re-working of the

provided files, following the procedure of McCullough, McGeary, and Harrison (2006).14

One dimension where we are unable to follow the authors exactly is the software ver-

sion they use. To execute the replications, we make use of the following software version-

operating system combinations: Dynare 4.3 and 4.4.2 (Windows), EViews 6 and 7 (Win-

dows), EViews 8 (Linux), Gauss 9.0.2 (Linux), Fortran f90 (Linux), Matlab R2008a and

R2012a and R2013a (Windows), Matlab R2010a and R2012a (Linux), OX 6.30 (Windows),

Oxmetrics 6.30 (Windows), Stata 11.0 and 13.1 (Windows), Stata 13.0 (Windows and Linux),

R 2.15.1 and 3.0.1 and 3.0.2 and 3.0.3 and 3.1.0 (Linux), and RATS 7.10 (Linux).15 When

available in the readme, we attempt to run the software version-operating system combina-

tion specified by the authors. When the replication files fail to execute on a given software

version-operating system combination, the author readme did not specify a particular soft-

ware version-operating system combination, and it appeared that the data and code were

complete, we email the authors to find out which combination they use.

3 Results

This section presents summary statistics of our replication attempts.16

12This definition corresponds to a rating of three out of five, “minor discrepancies,” or better by Glandon(2010), and “partially successful replication” or better by McCullough, McGeary, and Harrison (2006).

13This definition is less stringent than the definition for replication success of McCullough, McGeary, andHarrison (2006, 2008)

14McCullough, McGeary, and Harrison (2008), in their appendix, suggest that “the author [whose study isbeing replicated] provides code such that data and code, when placed in the same subdirectory, will execute;and that the output from doing this also will be provided... and produces the results in his paper,” whichimplies that replication files should contain the data and code that requires no re-working. If the code isclearly missing the ability to replicate results, then we do not attempt to re-code the procedures ourselves.

15We check the replication results of a small sample of selected papers across different versions of Matlab forWindows and find very minor differences. None of the differences in results across different versions of Matlabare qualitatively significant. The web appendix lists the software version-operating system combination weuse for each successfully replicated paper.

16Interested readers can find detailed results for each paper we successfully replicate in the web appendixon Chang’s website, https://sites.google.com/site/andrewchristopherchang/research.

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Table 1 lists the papers we successfully replicate. Table 2 breaks down our replication

results by journal type. Panel A of Table 2 shows that our overall replication success rate is

29 of 67 papers (43%).

Table 2, Panel B shows that we successfully replicate 23 of 39 papers (59%) from journals

that require data and code replication files. This rate compares to 6 of 28 (21%) of the papers

from journals that do not require such files, shown in Table 2, Panel C. These replication

rates are similar when we only consider papers with publicly available data: we successfully

replicate 23 of 35 (66%) of the papers from journals with mandatory data and code policies

and 6 of 26 (23%) of the papers from journals without such policies. The presence of a

mandatory data and code policy does not necessarily imply a causal relationship from the

policy to successful replication. Authors select which journals to submit papers to, taking

into account idiosyncratic journal policies such as mandatory submission of replication data

and code. However, we find that it is significantly easier to replicate published research that

comes from journals that require authors to submit their data and code.

Table 3, Panel A provides explanations for why we are unable to replicate papers ac-

cording to four broad classifications: “missing public data or code,” “incorrect public data or

code,” “missing software,” or “proprietary data.” Panel B provides the breakdown for jour-

nals that require data and code. Panel C shows the results for journals that do not require

data and code.

From Table 3, Panel A we find that we are unable to replicate 21 papers because of

“missing data or code,” which constitutes the majority of our failed replications (55%).

As we outline in our methodology, for each of these unsuccessful replications we attempt

to secure data and code from the authors by visiting their personal websites, visiting the

journal websites (when the journal requires authors to submit data or code), and sending

email requests. We classify an unsuccessful replication as “missing data or code” when at

least one of two events occur: (1) the replication code file(s) are clearly missing necessary

author-written functions for a subset or all of the key results or (2) the replication data

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file(s) are missing at least one variable. If the replication data has a shorter data sample

than reported in the paper, then we still attempt the estimation and do not necessarily

classify the paper as “missing data or code.”

We are unable to replicate 9 papers (24% of failed replications) because of “incorrect

data or code.” We classify an unsuccessful replication as “incorrect data or code” when all

variables are present in the dataset and the authors self-identify code for each of the key

figures and tables we attempt to replicate. The author-provided code may finish executing

and give different results or the code may not finish executing and still fall into this category.

We believe we do not have the needed software to run two papers (Senyuz, 2011; Jermann

and Quadrini, 2012) because we are unable to locate a necessary packaged function in our

versions of the appropriate software, because of significant syntax changes between software

versions, or because the authors declared that they use a particular software version and we

are aware that our software would not be compatible. However, it is tricky differentiating be-

tween an unsuccessful replication due to “incorrect data or code” or due to “missing software.”

Because the implementation of packaged functions may differ across software versions even

without syntax changes, we believe the number of failed replications we classify as “missing

software” is a lower bound. It is possible that a paper we classify as “incorrect data or code”

is actually replicable with the appropriate operating system-software combination, so some

of the papers that we classify as “incorrect data or code” may belong in the “missing software”

category. However, we cannot verify this statement without additional documentation.

Table 4 shows our summary statistics for successful replications independent of the au-

thors versus replications that were successful with the author’s help. Overall, we find that

contacting the authors marginally improves our success rate for replication. Of the 29 suc-

cessful replications, we complete 22 without any help from the authors.

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4 Conclusion and Recommendations

In this article, we attempt to replicate 67 papers from 13 well-regarded economics journals

using author-provided data and code replication files. Improving on existing work evaluating

the state of replication in economics, our sampling frame is broader across different journals

and covers a large number of original research articles. We replicate 22 of 67 papers (33%)

by using only the authors’ data and code files, and an additional 7 papers (for a total of

29 papers, 43%) with assistance from the authors. The most common cause of our inability

to replicate findings is that authors do not provide files to the journal replication archives,

which constitutes approximately half of our failed replication attempts (21 of 38 papers,

55%). Because we are able to replicate less than half of the papers in our sample, we

conclude that economics research is generally not replicable.

We now turn to some recommendations that we feel would improve the ability for re-

searchers to replicate and extend published articles, largely echoing the recommendations of

McCullough, McGeary, and Harrison (2006).

• Mandatory data and code files should be a condition of publication.

Our replication success rate is significantly higher when we attempt to replicate papers from

journals that have a mandatory replication data and code submission policy. We believe that

replication files need to encompass both data and code. As shown in Table 2, the data-only

archives at Economic Journal and Journal of Applied Econometrics only allow for replication

of 4 of 20 papers (20%) that use non-confidential data, compared to the replication success

rate of 23 of 35 papers (66%) that use non-confidential data from journals that require both

data and code.

• An entry in the journal’s data and code archive should indicate whether a paper without

replication files in the journal’s archive is exempt from the journal’s replication policy.

Among papers that we believe were subject to a mandatory data and code policy, we are

unable to acquire replication files for 6 of 35 papers (15%) even after emailing, and often

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receiving a response from, the authors. However, we are unsure whether these six papers are

exempt from their respective journal’s mandatory data and code policies, and the authors

did not volunteer whether their papers are exempt in response to our requests for replication

files. Therefore, we suggest that journals include an exemption entry in their replication

archives. This note in the replication archives would have four virtues: (1) it is low-cost for

the journal, (2) it would save authors who are exempt from submitting replication files from

needing to respond to queries about replication files, (3) it would save would-be-replicators

from searching for replication files for papers that are exempt from the journal’s policy, and

(4) it would identify those authors who are not compliant with the journal’s mandatory data

and code policy.

• Readme files should indicate the operating system-software version combination used

in the analysis.

We attempt to use the operating system-software version combination reported by the au-

thors in their readme files, but we notice that very few readmes include the operating system-

software version combination used to conduct their analysis. When we ask authors about the

operating system or software version they use to run their models, most authors do not recall

this information. Although it is not a focus of our paper, we notice minor discrepancies for a

selected subset of papers when running programs on different versions of Matlab (although

the discrepancies are not large enough to change the key qualitative results).

• Readme files should contain an expected model estimation time.

Many macroeconomic models are estimated with Bayesian (i.e., Markov Chain Monte Carlo)

methods, which can take a considerable amount of processing time to execute even under the

best of circumstances. We encountered a few instances where we believed an estimation was

executing, only to find out weeks later that the programs were stuck in an infinite loop and

were supposed to run in much less time. In addition, frequently programs are not written

to optimize computation time and also frequently written without a progress bar, so there

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is no way to track the expected completion time of estimation. A low-cost alternative to a

progress bar is simply writing the expected estimation time in the readme file.

• Code that relies on random number generators should set seeds and specify the random

number generator.

Optimization algorithms often rely on a set of initial conditions, which are commonly speci-

fied through a random number generator. For any research that relies on a random number

generator, replication requires the same set of numbers that are generated in the published

article.

• Readme files should clearly delineate which files should be executed in what order to

produce desired results.

Occasionally, we are presented with replication data and code that requires files to be exe-

cuted in a particular order to furnish published results. In cases where the execution order

is critical but unspecified, we spend a considerable amount of time attempting to determine

the proper order of execution and, in some cases, ultimately fail to do so.

We now turn to two recommendations that will improve the ability of researchers to

extend published work, in addition to merely replicating it.

• Authors should provide raw data in addition to transformed series.

While only the transformed data are needed to conduct replication of published results,

raw data facilitate potential extensions of research. For example, raw data allow for the

investigation of the effect that revisions to macroeconomic data have on previously published

research, as in Croushore and Stark (2003) and Chang and Li (2015).

• Programs that replicate estimation results should carry out the estimation.

We notice that the replication files for a few papers run smoothly and exactly furnish the

results of the tables and figures as published. However, oftentimes the results in tables and

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figures depend on a model’s parameters being estimated. Some of these replication files,

instead of estimating the models, take the relevant parameters as given to produce results

in tables and figures. For verification of published results, and particularly for purposes of

extending research, we assert that code that actually estimates the relevant models would

be far more useful.

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Table 1: Successfully Replicated PapersAuerbach and Gorodnichenko (2012)Barro and Redlick (2011)Baumeister and Peersman (2013)Canova and Gambetti (2010)Carey and Shore (2013)Chen, Curdia, and Ferrero (2012)Clark and McCracken (2010)Corsetti, Meier, and Müller (2012)D’Agostino and Surico (2012)Den Haan and Sterk (2011)Favero and Giavazzi (2012)Gabaix (2011)Hansen, Lunde, and Nason (2011)Heutel (2012)Inoue and Rossi (2011)Ireland (2009)Kilian (2009)Kormilitsina (2011)Krishnamurthy and Vissing-Jorgensen (2012)Mavroeidis (2010)Mertens and Ravn (2011)Mertens and Ravn (2013)Morley and Piger (2012)Nakov and Pescatori (2010)Ramey (2011)Reis and Watson (2010)Romer and Romer (2010)Schmitt-Grohé and Uribe (2011)Schmitt-Grohé and Uribe (2012)

We replicate the corrected results of Auerbach and Gorodnichenko (2012) found in Auerbachand Gorodnichenko (2013).

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Table 2: Replication Sample and Results By JournalPapers Papers With Total

Replicated Public Data PapersSuccessfully

Panel A: All Journals 29 61 67Panel B: Journals that Require Data and Code:American Economic Journal: Economic Policy 2 4 4American Economic Journal: Macroeconomics 3 3 4American Economic Review 5 8 10Canadian Journal of Economics 0 0 1Econometrica 3 3 3Journal of Political Economy 1 1 1Review of Economic Dynamics 4 7 7Review of Economic Studies 0 2 2Review of Economics and Statistics 5 7 7Total for Journals that 23 35 39Require Data and CodePanel C: Journals that Do Not Require Data and Code:American Economic Review: P&P 0 4 5Economic Journal 3 10 11Journal of Applied Econometrics 1 10 10Quarterly Journal of Economics 2 2 2Total for Journals that 6 26 28Do Not Require Data and Code

Journal of Applied Econometrics requires data only. Economic Journal currently requiresdata and code, but the papers in our sample were not subject to a data and code policyaccording to the Economic Journal’s editorial office.

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Table 3: Failed Replication Results, Including Causes of Failure, By Journal TypePercentage of

Paper Count SamplePanel A: All Journals

Replication Unsuccessful 38 100Unsuccessful Because of:Missing Public Data or Code 21 55Incorrect Public Data or Code 9 24Missing Software 2 5Proprietary Data 6 16

Panel B: Journals With Mandatory Data and Code PoliciesReplication Unsuccessful 16 100Unsuccessful Because of:Missing Public Data or Code 6 38Incorrect Public Data or Code 5 31Missing Software 1 6Proprietary Data 4 25

Panel C: Journals Without Mandatory Data and Code PoliciesReplication Unsuccessful 22 100Unsuccessful Because of:Missing Public Data or Code 15 68Incorrect Public Data or Code 4 18Missing Software 1 5Proprietary Data 2 9

Table 4: Successful Replication Results By Journal TypePercentage of

Paper Count SamplePanel A: All Journals

Replication Successful 29 100Successful:With Contacting Authors 7 24Without Contacting Authors 22 76

Panel B: Journals With Mandatory Data and Code PoliciesReplication Successful 23 100Successful:With Contacting Authors 3 13Without Contacting Authors 20 87

Panel C: Journals Without Mandatory Data and Code PoliciesReplication Successful 6 100Successful:With Contacting Authors 4 67Without Contacting Authors 2 33

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